Mrs Tang is 56 years old and her niece is 8 years old now. In how many years' time will Mrs Tang be thrice as old as her niece?
| |
Mrs Tang |
Her niece |
Difference |
| Before |
56 |
8 |
48 |
| Change |
+ ? |
+ ? |
|
| After |
3 u |
1 u |
2 u |
The difference in the age between Mrs Tang and her niece remains unchanged.
Difference in their age at first
= 56 - 8
= 48
Difference in their age in the end
= 3 u - 1 u
= 2 u
2 u = 48
1 u = 48 ÷ 2 = 24
Number of years time that Mrs Tang will be thrice as old as her niece
= 1 u - 8
= 24 - 8
= 16
Answer(s): 16
